Semiconductor device test system with test interface means

Abstract

A semiconductor device test system has an interface for use with a semiconductor device test method, and a semiconductor device test method. In a first mode of an interface, in reaction to test signals corresponding to a test standard, for example, a JTAG test standard, and received by the interface from a test device, the interface outputs signals corresponding to the test standard to a semiconductor device to be tested. In a second mode of the interface, in reaction to test signals corresponding to the test standard and received by the interface from a test device, the interface outputs signals that do not correspond to the test standard to a semiconductor device to be tested.

1. A semiconductor device test method comprising:
 in a first mode of an interface device, in reaction to test signals corresponding to a test standard and received by the interface device from a test device, the interface device outputting signals corresponding to the test standard via at least one signal line to a semiconductor device to be tested, and 
 in a second mode of said interface device, in reaction to test signals corresponding to the test standard and received by said interface device from a test device, said interface device outputting signals that do not correspond to the test standard via the at least one signal line to the semiconductor device to be tested. 
 
     
     
       2. The method according to  claim 1  further comprising providing a register corresponding to the test standard on said interface device, said register being addressed by said test device as if the register were provided on the semiconductor device to be tested. 
     
     
       3. The method according to  claim 2 , wherein the register is a JTAG IEEE standard 1149.1-1990 register. 
     
     
       4. The method according to  claim 1 , wherein the test standard is a JTAG IEEE standard 1149.1-1990. 
     
     
       5. The method according to  claim 2 , further comprising physically providing the register on said interface device and logically assigning the register to said semiconductor device to be tested. 
     
     
       6. The method according to  claim 1 , wherein the test signals received by said interface device are JTAG IEEE standard 1149.1-1990 test signals. 
     
     
       7. The method according to  claim 1 , wherein the signals output by said interface device in the second mode do not correspond to the test standard with respect to data rate, or clock rate, or signal duration. 
     
     
       8. The method according to  claim 1 , wherein the signals output by said interface device in the first mode are transmitted via JTAG IEEE standard 1149.1-1990 signal lines from said interface device to said semiconductor device to be tested. 
     
     
       9. The method according to  claim 8 , further comprising transmitting the signals output by said interface device in the second mode from said interface device to said semiconductor device to be tested via one or a plurality of lines that are provided in addition to the JTAG IEEE standard 1149.1-1990 signal lines. 
     
     
       10. The method according to  claim 8 , further comprising transmitting the signals output by said interface device in the second mode from said interface device to said semiconductor device to be tested via said JTAG IEEE standard 1149.1-1990 signal lines. 
     
     
       11. An interface device, adapted to:
 in a first mode, in reaction to test signals received from a test device and corresponding to a test standard, output signals corresponding to the test standard to a semiconductor device to be tested; and 
 in a second mode, in reaction to test signals received from a test device and corresponding to the test standard, output signals that do not correspond to the test standard to a semiconductor device to be tested. 
 
     
     
       12. A semiconductor device test system comprising:
 at least one semiconductor device to be tested; and 
 an interface device by which, in a first mode, in reaction to test signals corresponding to a test standard and received from a test device, signals corresponding to the test standard are output to the semiconductor device to be tested via at least one signal line, and by which, in a second mode, in reaction to test signals corresponding to the test standard and received from a test device, signals that do not correspond to the test standard are output to the semiconductor device to be tested via the at least one signal line. 
 
     
     
       13. The test system according to  claim 12 , in which a register corresponding to the test standard is provided on said interface device, said register being designed and equipped such that it is adapted to be addressed by said test device as if the register were provided on said semiconductor device to be tested. 
     
     
       14. A integrated circuit, comprising:
 means which in a first mode of the integrated circuit, in reaction to test signals received from a test device and corresponding to a test standard, output signals corresponding to the test standard to a semiconductor device to be tested;, and 
 means in which a second mode of the integrated circuit, in reaction to test signals received from a test device and corresponding to the test standard, output signals that do not correspond to the test standard to a semiconductor device to be tested.